1. Field of the Invention
Embodiments of the present disclosure are related to power supply, and in particular to a system and method for supplying power to an electronic device.
2. Description of Related Art
Portable digital electronic devices in everyday use rely on portable power storage to function continuously. However, portable power storage, such as a battery, requires replacement or recharging when supply falls below a working threshold. Usually such batteries utilize direct current (DC), power supply estimated by a voltage level of the battery.
Portable digital electronic devices, such as mobile phones largely, use the same working voltage of 3.6 Volts (V), with most employing flat batteries attached to one end of the device. Among numerous charging technologies, connection of an adapter of the device to a power jacket is commonly used, wherein an adapter connects the battery and an alternating current (AC) electric grid, and converts the supplied AC current of 220V/110V to direct current (DC) of 5V to recharge the battery. Other technologies utilize conversion of kinetic energy to DC power by hand movement, conversion of solar power to DC power by solar panel, and conversion of wind energy to DC power, and many others. However, all require bulky conversion and charging systems, decreasing the portability and convenience of the portable digital electronic device.
Many mobile phones currently use Universal Serial Bus (USB) interfaces as a standard data and power supply connection based on information disclosed by the Open Mobile Terminal Platform (OMTP) forum. Other portable digital electronic devices besides mobile phones use the USB connector interface as well. Nonetheless, there is currently no explicit method for recharging one portable digital electronic device from another by a USB connector.
Therefore, what is needed is a system and method for supplying power from a portable device, particularly for supplying power from one battery to another.